Kůže je důležitý bariérový orgán. Její anatomická a funkční zralost je jedním z limitů přežití novorozence a její stav značně ovlivňuje fyzickou a psychickou kvalitu života po celý život člověka. Četná onemocnění kůže vznikají na genetickém podkladě. Znalost vývojových mechanismů a souvislostí je proto důležitá i v běžné dermatologické praxi. Dermatolog navíc může tuto znalost využít při hledání souvislostí kožních a mimokožních projevů, a může tak sehrát důležitou roli v časné diagnostice některých vrozených onemocnění.
Skin is an important barrier organ. Anatomically and functionally mature skin is not only limiting for survival of a newborn, but skin integrity influences significantly physical as well as psychical quality of life in humans. Many skin diseases are determined genetically. Therefore, the knowledge of skin development mechanisms and its connections is important in medical practice and can be used by dermatologists while correcting cutaneous and non-cutaneous manifestations, which can play a major role in the early diagnostics of inherited diseases.
The skin surface is modified by numerous appendages. These structures arise from epithelial stem cells (SCs) through the induction of epidermal placodes as a result of local signalling interplay with mesenchymal cells based on the Wnt-(Dkk4)-Eda-Shh cascade. Slight modifications of the cascade, with the participation of antagonistic signalling, decide whether multipotent epidermal SCs develop in interfollicular epidermis, scales, hair/feather follicles, nails or skin glands. This review describes the roles of epidermal SCs in the development of skin adnexa and interfollicular epidermis, as well as their maintenance. Each skin structure arises from distinct pools of epidermal SCs that are harboured in specific but different niches that control SC behaviour. Such relationships explain differences in marker and gene expression patterns between particular SC subsets. The activity of well-compartmentalized epidermal SCs is orchestrated with that of other skin cells not only along the hair cycle but also in the course of skin regeneration following injury. This review highlights several membrane markers, cytoplasmic proteins and transcription factors associated with epidermal SCs.
- MeSH
- buněčná diferenciace genetika MeSH
- epidermální buňky metabolismus patologie MeSH
- epidermis metabolismus patologie MeSH
- kmenové buňky metabolismus patologie MeSH
- kůže patologie MeSH
- lidé MeSH
- signální transdukce genetika MeSH
- vlasový folikul metabolismus patologie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
Dermal fibroblasts seem critical for epidermal maturation and differentiation and recent work demonstrated that diseased fibroblasts may drive pathophysiological processes. Nevertheless, still very little is known about the actual crosstalk between epidermal keratinocytes and dermal fibroblasts and the impact of dermal fibroblasts on epidermal maturation and differentiation. Aiming for a more fundamental understanding of the impact of the cellular crosstalk between keratinocytes and fibroblasts on the skin homeostasis, we generated full-thickness skin equivalents with and without fibroblasts and subsequently analysed them for the expression of skin differentiation markers, their barrier function, skin lipid content and epidermal cell signalling. Skin equivalents without fibroblasts consistently showed an impaired differentiation and dysregulated expression of skin barrier and tight junction proteins, increased skin permeability, and a decreased skin lipid/protein ratio. Most interestingly, impaired Ras/Raf/ERK/MEK signalling was evident in skin equivalents without fibroblasts. Our data clearly indicate that the epidermal-dermal crosstalk between keratinocytes and fibroblasts is critical for adequate skin differentiation and that fibroblasts orchestrate epidermal differentiation processes.
- MeSH
- buněčná diferenciace MeSH
- epidermální buňky metabolismus patologie MeSH
- epidermis metabolismus MeSH
- fibroblasty metabolismus MeSH
- homeostáza genetika fyziologie MeSH
- keratinocyty metabolismus patologie MeSH
- kožní absorpce MeSH
- kůže metabolismus patologie MeSH
- lidé MeSH
- permeabilita MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
